Method and process for video over IP network management

Abstract

The invention is directed to systems and methods for testing performance of a packet-based network. In particular, the invention can be used to measure latency, packet loss, jitter and out-of-sequence packets. To measure the one-way timing issues such as the one-way latency, a highly accurate clock can be placed at the packet source and destination so that the time difference can be calculated with accuracy.

1 . A method for measuring performance of a packet-based network comprising: 
 generating a sequence of packets of variable size at a source,    transmitting the sequence of packets from the source,    storing the transmission time of a packet selected from the sequence of transmitted packets,    receiving the selected packet at a destination and storing the reception time of the selected packet, and    calculating the time difference between the transmission of the selected packet and the reception of the selected packet.    
   
   
       2 . The method of  claim 1  wherein the transmission time of the packet is received from a clock synchronized to an external time source.  
   
   
       3 . The method of  claim 2  wherein the external time source is a GPS clock.  
   
   
       4 . The method of  claim 2  wherein the external time source is a CDMA clock.  
   
   
       5 . A method for measuring performance of a packet-based network comprising: 
 generating a sequence of packets of variable size at a source,    transmitting the sequence of packets from the source and storing a parameter from a packet selected from the sequence at the time of transmission,    receiving the selected packet at a destination and storing a parameter from the packet selected from the sequence at the time of reception, and    calculating a network performance value based on a comparison of the parameter stored at the time of transmission and the parameter stored at the time of reception.    
   
   
       6 . The method of  claim 5  wherein the network performance value represents latency.  
   
   
       7 . The method of  claim 5  wherein the network performance value represents packet loss.  
   
   
       8 . The method of  claim 5  wherein the network performance value represents jitter.  
   
   
       9 . The method of  claim 5  wherein the network performance value represents out-of-sequence arrival.  
   
   
       10 . A system for measuring performance of a packet-based network comprising: 
 a packet sequence generator for generating a sequence of packets of variable size at a source,    a packet sequence transmitter for transmitting the sequence of packets from the source,    a receiver for receiving a packet selected from the transmitted sequence at a destination,    a database for storing the transmission time and reception time of the packet selected from the sequence of transmitted packets, and    a time difference calculator for calculating the time difference between the transmission of the selected packet and the reception of the selected packet.    
   
   
       11 . The system of  claim 10  further comprising a clock synchronized to an external time source for acquiring the transmission time of the selected packet.  
   
   
       12 . The system of  claim 10  wherein the external time source is a GPS clock.  
   
   
       13 . The system of  claim 10  wherein the external time source is a CDMA clock.  
   
   
       14 . A system for measuring performance of a packet-based network comprising: 
 a packet sequence generator for generating a sequence of packets of variable size at a source,    a packet sequence transmitter for transmitting the sequence of packets from the source,    a receiver for receiving a packet selected from the transmitted sequence at a destination,    a database for storing a first parameter from the selected packet at the time of transmission and a second parameter from the selected packet at the time of reception, and    a network performance value calculator for calculating a value based on a comparison of the parameter stored at the time of transmission and the parameter stored at the time of reception.    
   
   
       15 . The system of  claim 14  wherein the network performance value represents latency.  
   
   
       16 . The system of  claim 14  wherein the network performance value represents packet loss.  
   
   
       17 . The system of  claim 14  wherein the network performance value represents jitter.  
   
   
       18 . The system of  claim 14  wherein the network performance value represents out-of-sequence arrival.